An unstable weak acid formed when sulfur dioxide dissolves in water. It is used as a reducing and bleaching agent.
- ‘Common reductants are the active metals, hydrogen, hydrogen sulfide, carbon, carbon monoxide, and sulfurous acid.’
- ‘Antoine-Laurent Lavosier experimented with volatile sulphurous acid which readily yields the gas sulfur dioxide.’
- ‘In one of his lectures, John Tyndall created an ‘artificial sky’ by passing a beam of light through a dish of sulfurous acid: the gas was invisible at first, then became an intense sky-blue, followed by white, and finally a cloudy white.’
- ‘Sulphur dioxide (which forms sulphurous acid in water) is used for commercial dried fruit.’
- ‘Sorbic acid, a preservative; tartaric acid, a stabiliser; and citric and sulphurous acid - that's sulphur dioxide to you and me - are all regularly added during the wine making process.’
We take a look at several popular, though confusing, punctuation marks.